The present invention relates, in general, to electrically conductive interconnects, and more particularly, to controlling electromigration in electrically conductive interconnects.
Semiconductor device manufacturers are constantly striving to reduce device sizes and to increase operational performance thereby increasing the current densities at which these devices operate. During device operation at high current densities, metal atoms migrate from one portion of an electrically conductive interconnect to another portion. As those skilled in the art are aware, migration of metal atoms, commonly referred to as electromigration, decreases the reliability of the semiconductor devices. More particularly, the movement of metal atoms creates voids in one portion of the electrically conductive interconnect and hillocks, i.e., a pileup of metal atoms, in another portion of the electrically conductive interconnect. The voids may result in open circuits, whereas the hillocks may result in one or more electrically conductive interconnects becoming shorted.
Accordingly, it would be advantageous to have a method and a structure for improving semiconductor device reliability by controlling the migration of metal atoms. It would be of further advantage for the method to be compatible with conventional semiconductor processing techniques.